Telephone system.



E. YAXLEY.

TELEPHONE SYSTEM.

APPLICATION FILED JAN. 18, 1909.

Patented June 15,1909.

I I WI I frizes wwf WITNESSES WMJ? k 3% EUNITED STATES PATENT OFFICE.

ERNEST E. YAXLEY, OF CHICAGO, ILLINOIS, ASSIGNOR TO MONARCH TELEPHONEMANU- FAOTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OFILLINOIS.

TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented June 15, 1909.'

Application filed .ianuary 18, 1909.: Serial No. 472,809.

and exact description, reference being had to v the accompanyingdrawings, forming a part of this specification.

. Myinventionrelates to telephone exchange systems, and has for itsobject the provision of a system wherein a common or central source ofdirect current may be employed to advantage in imparting magnetism tothe telephone receivers, so that such receivers nee not have permanentmagnets included in their construction, whereby objections whicharefamiliar to those skilled in the art are avoided.

I am aware that it is old to have a common battery of a telephoneexchange system supply current to coils of telephone receivers avin softiron cores, which coils do not errnit 0 the assage of voice currents, anto provide sue receivers with coils that are restricted to the receptionof voice currents, these latter coils being incapable of receivingdirect current from the common source. In such a system ofthe prior artthe coils that are adapted to receive the direct or continuous currentfrom the commonsource, are in the nature of impedance coils, so that'thevoice currents are prevented from flowing to a material extenttherethrough.

In the system of my invention, the coils that receive the voice currentsare particularly and especially designed also to receive direct currentfrom the common source, so that these telephone current receiving coilsmay supplement the companion coils in the polarization of the receivers,due to the flow of direct current. In the system of my invention,therefore, the telephone current receiving coils are well ada ted to thepassage of steady currents for t e purpose stated, and, in the preferredembodiment of the invention, offer less resistance to the flowof steadycurrent than do thecompanion coils that, in the preferred embodiment ofthe invention, are adapted to permit of the passage of little or notelephonic currents, but

are restricted preferably practically to .the passage of direct current.

' As another feature of the preferredforrn.

of my invention, I cause both kinds of winding of each receiverto conveydirect currentto the transmitter in association therewith, so that thecommon battery not only per forms the functions which have been-described in connection with the'receiver, but also supplies thetransmitter with straight current.

As another feature of my invention, the two kinds of winding of eachreceiver are in-. cluded in parallel relation with each other andtogether are included in serial relation with the common source ofcurrent and the transmitter associated with the receiver. By includingthe two windings ofeach receiver in parallel relation with each otherand the two in parallel in serial relation-With the common battery, thejoint resistance of said winding, which is opposed to the batterycurrent, is much less than the resistance that would be offered to suchcommon battery current if that winding of each receiver which is to besubject to the telephone currents were not traversed by direct currentfrom the battery.

If in the system of, the prior art, the resistance of the impedance coilis ,sufficiently increased properly to revent the passage of voicecurrents theret rough, a correspondingly increased obstruction isvprovided to the passage of current from the common battery, whichcannot be remedied by the system of the prior art but is remedied by the7 system of my invention, as the parallel path which I provide about theimpedance coil, and which includes the voice current receiving winding,affords passage for the direct current, so that the increased resistancein the impedance coil is compensated for and the objectionable increasein the obstruction to the path of the direct current is avoided. I amalso aware-that it is old to have a single receiver winding provided forthe double purpose ofreceiving voice currents and for receiving directcurrents, to enable such single winding to impart magnetism to thereceiver, due to the direct current, and to enable this magnetismto bemodified by the voice currents traversing this single winding, but insuch a system the single Winding must, be of low resistance in order toafford the' proper passage of direct current for-polarizmg the receivermagnet and for energizing the transmitter and therefore, owin to thephysical-limitations as to the size. 0 there high to enable it toperform its' functions properly. Bymak1ng the telephone currentreceiving W1I1(i11g of lower ohmic resistance vthan'the impedancewinding, I ain enabled to relieve the impedance winding of arelativelygreat proportion of the total direct current flowing through the linefor the energization of the transmitter. By doing this I increase theimpedance of the impedance winding, ,because, as is well known, the imed ance of any coil is greater as the magnetic dhx through its core issmaller. As the magnetism in a core lpproaches the saturation point ofthat core,

a t ere is a marked reduction of impedance, and it is for this reasonthat I allow the voice current receiving winding to carry a largeproportion of the current.-- The telephone current receiving windingthus aids in the polarization of the core, and at the same time aliowsa'greater effective impedance to its companion winding. As the impedancewinding and the voice current-receiving winding are each wound in thesame direction", the polarizingi'nfluence of the two, due to the flow ofdirect current through them,-are.cu'mulative, and by virtue of the factthat the voice current receiving winding is close to the diaphragm, thesteady polarization of the core is effective to its extreme end, whichis not the casein those receivers'of the prior art inwhich steady'cuFrentisiexcludedfrom the voice current receiyin winding. In my receiver,therefore,

both 0 the coils contribute in marked degree.

to the "pol'arizi of the receiver core, and while the two coi s are inshunt, the very h gh relative 1m ed'ance of the impedance winding servesto s unt practically all of the voice currents through the voice currentreceiving winding,,where they will exert a maximum efiect on the d aphram, but any voice currents that do passt rough the, im edance windin arenot lost in their effect, ut add their eifect to the effect reduced bythe voice currents in the telep one current re-- ceivin winding.

I wi l explainmy invention more fully by reference to the accompanyingdrawing, diagrammatically illustrating1 station in connection wit a corcircuit at an exchange. The telephone line illustrated a a tele honesub- 7 is a metallic circuit line, to which, however, I do not wish tobe limited, whose sides 1 and 2 terminate respectively in tip and sleevecontacts 3 and 4 of aspring jack or jack-switch ized core, has a softiron core provided with an impedance winding 9, through which circuit isdesirably only established when'connection is established with the lineat the exchange, so that said receiver is not materially magnetized whenthe circuit of the line is open and is suiiiciently ener ized when thecommon battery 7 is in close relation with the line, so that themagnetism thus imparted to the receiver is equivalent to and acts inplace of the magnetism that is imparted to those receivers 'of the priorart that include permanent magnets in their construction. All of thewinding 9 which is to afford -impedan'ce, is desirably disposed aboutthe coreof the receiver, though I' do not wish to be limited in allembodiments of my invention to this arrangement.-

The winding of the receiver that is to be responsive to incoming voicecurrents for the pu ose of enabling the receiver to act as suc 1, isindicated at 10 in dis osition about the same core that carries t-ewinding 9. The coil 10,. however, may be closer to the diaphr m 10 thanthe winding 9, the winding 10- eing in multiple relation with the.winding. 9, both windings 9 and 10 being in serial relation with thebattery and the transmitter 5. Each receiver thus has two cir- 1cuitsthat are in parallel, one of the circuits including winding whichaffords impedance to the voice'currents and produces magnetism whichtakes the'place of the magnetism hitherto furnished by a permanentmagnet. The circuit which includes the impedance winding 9, desirablyossesses an ohmic re- 7 sistance of fifty-five o nns, while theremaining receiver circuit affords an ohmic rcsistance of forty-fiveohms, so that the latter circuit, while being adapted to permit of thepassa e of voice currents, preferably aiiords a pat i of lowerresistance to the direct cur rent than does the former circuit. Thejoint resistance afforded by the two circuits of a each receiver issufliciently low to permit cl the proper. passage of current from'thchat-- tel-y 7 over the line and through the transmitter.

" ratus at the exchange, nor other apparatus at The switch arrangementat the substa tion may be'suited to the exchange system. I have shown atelephone switch-hook 11 having an upper contact to bring the sides ofthe line in conductively continuous relation when the receiver isremoved.

I have shown at the sub-station a signal bell 12 of high impedance,bridged between the sides of the line, the bell bridgeincluding thecondenser 13.

I have not indicated any signaling appathe exchange, as suchillustration is not needed for the of my invention and as theapplication of the apparatus of the system of my invention will bereadily understood by those skilled in the art.

It is obvious that changes may readily be made in the preferredembodiment of the invention herein shown and particularly described,without departing from the spirit of the invention, and I donot,therefore, wish to be limited to the precise features illustrated, but,

Having thus described my invention, I claim as new and desire to secureby Letters Patent 1. A telephone system including a telephone lineextending between a telephone station and an exchange, a source ofdirect current at the exchangefor-supplying current to the telephoneline, the telephone receiver at said station including a magnetizablecore and having'two circuits in parallel relation with each other and inserial relation with the line and both adapted to be traversed bycurrent from said source of direct current, and each including a windingserving to magnetize the receiver core, due to the passage of the directcurrent, one of said windings possessing impedance to obstruct the flowof voice current-s and the other of said windings being adapted topermit of the passage of voice currents, 'the transmitter at saidstation being in serial relation with the circuits of the receiver takentogether, and thereby being adapted to be supplied also with currentemanating from the source of direct current.

2. A telephone system including a telephone line extending between atelephone station and an exchange, a source of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at said station having two receiver energizing circuits inparallel relation with ecah other and in serial relation with the lineand both adapted to be traversed by direct current from said source ofdirect current to energize the receiver, and one adapted to be traversedby voice currents while the other possesses impedance to restrict theflow of voice currents, the" transmitter at said station being in serialrelation with the circuits purpose of an understanding.

being adapted to be supplied also with current emanating from the sourceof direct current.

3. A telephone system including a telephone line' extending between atelephone station and an exchange, a source of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at said station including a magnetizable core and having twocircuits in parallel relation with each other and in serial relationwith the line and both adapted to be traversed by current fromsaidsource of direct current, and each including a winding serving tomagnetiz'e the receiver core, due to the passage of the direct current,one of said windings possessing impedance to obstruct the flow of voicecurrents and the other of said windings being adapted ,to permit of thepassage of voice currents, the transmitter at said station being inserial relation with 'he circuits of the receiver taken together. andthereby being adapted to be supplied also with current emanating fromthe source of direct current, the receiver circuit which is subject tothe voice currents possessing lower ohmic resistance than the companionreceiver circuit.

4. A telephone system including a telephone line extending between atelephone station and an exchange, a source of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at said station having two receiver energizing circuits inarallel relation with each other and in seria relation with the line andboth adapted to be .traversedby direct current from said source ofdirectcurrent to energize the receiver, and one adapted to be traversedby voice currents while the other possesses impedance to restrict theflow of voice currents, the transmitter at said station being in serialrelation with the circuits being adapted to be supplied also with current emanating from the source of direct current, the receiver circuitwhich is subject to the voice currents possessing lower olnnicresistance than the companion receiver circuit.

5. A telephone system including a telephone line extending from atelephone station and an exchange, a source of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at said station'including a magnetizable core and having twocircuits in parallel relation with each other and in serial relationwith the line and both adapted to be traversed by current from saidsource of direct current, and each including a winding serving to magnetize the receiver l the direct current, one of said windin s possessing impedance to obstruct the low of of the receiver taken together,and therebyof thereceiver taken together, and'thereb) core, due to thepassage ofcurrent atthe exchange for supplyingcurrentvoice currents andthe otherof said windings being adapted to permit of the passage ofvoice currents.

6. A telephone system including a tele-' phone line extending between atelephone station and an exchange, a source of direct to the telephoneline, the'telephone receiver at said station having two receiverenergizing circuits in parallel relation with each other and in serialrelation with the line and both adapted to be traversed by directcurrent relation with each other andin serial relation with the line andboth adapted to be trav-- ersed by current fromsaid source of directcurrent, and each including a winding serving to magnetize the receivercore, due to the passage of the direct current, one of said windingspossessing impedance toobstructthe flow of voice currents and't-he otherof said windings being adapted to permit of the passage of voicecurrents, the receiver circuit which is subject to the voice currentspossessing lower ohmic resistancethan the coinpanion receiver circuit.

8. A telephone system including a telephone line extending between atelephone station and anexchange, a source of direct current .at theexchange for supplying current to the telephone line, the telephonereceiver at said station having two recelverenergizing circuits inparallel relationwith each other and in serial relation with the lineand both adapted to be traversed by direct current from said source ofdirect current, to energize the receiver, and one adapted to betraversed by voice currents while the other possesses impedance torestrict the 'flow of voice currents, the receiver circuit which issubject to the voice currents possessing lower ohmic resistance than thecompanion receiver circuit.

9. A telephone system including a telephone line extending between atelephone station and an exchange, a source of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at said station including a magnetizable core and having twocircuits in parallel relation with each other and in serial relationwith the line and both adapted to be traversed by current from saidsource of direct current, and

each including a winding servingto' mag at said station havin netize thereceiver core, due to the assage of the direct current, one of said winings serving to permit of the passage of voicecur to be-supplied alsowith current emanating from, the source of direct current. I

10. .A telephone system including .a telephone lineextending between atelephone station and an exchange, a source of direct current at theexchange for-supplying current to the telephone line, the telephonereceiver g two receiver 'energizin circuits in paral el relation witheach otner and in serial relation with the lineand both adapted-tobetraversed by direct ourrent from said source-of direct current, to

energize the receiver, one of said windings serving to permit of thepassage ot voice currents, the transmitter at said stationbeing inserial relation with the circuits of the receiver taken together, andtherebyv being adapted to be supplied also with current emanating fromthe source ofdirect current.

11. A telephone system including a 'telephone line extending between atelephonestation and an exchange, a source. of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at'said station including a magnetizable core and having twocircuits in parallel relation with each other and in serial relationwith the line and both adapted to be traversed by current from saidsource of direct current,

and each including a winding serving to.

magnetize the receiver core, due to'the passage of the direct current,one of said wlndings serving to permit of the passage of voice currents,the transmitter at said station'being in serial relation with thecircuits of the receiver taken together, and thereby being adapted to besupplied also with current emanating from the source of direct current,the receiver circuit which is subject to the voice currents possessinglower ohmic resistance than the companion receiver circuit.

12. A telephone system including a telephone line extending betweena'telephone station and an exchange, a sourcevof direct current at theexchange for sup lying current to the telephone line, the te ephonereceiver at said station having two receiver energizing circuits inparallel relation with each. other and in serial'relation with the lineand both adapted to be traversed by direct current from said source ofdirect current, to energize the receiver, one of said windings servingto permit of the passage of voice currents, the transmitter at saidstation being in serial relation with the circuits of the receiver takentogether, and thereby being adapted to'be supplied also with current,emanating from the source of direct current, the restation and anexchange,

currents possessing lower ohmic resistance than the companion receivercircuit 13. A telephone system including a telephone line extendingbetween a telephone a source of direct current at the exchange forsupplying current to the telephone line, the telephone receiver at saidstation including a magnetizable core and having two circuits inparallel relation,

with each other and in serial relation with the line and both adapted tobe traversed by current from said source of direct current, and eachincluding a winding serving to magnetize the receiver core, due to thepassage of the direct current, one of said windings serving to permit ofthe passage of voice currents.

14. A telephone system including a telephone line extending between atelephone stationandan exchange, a source of direct current attheexchange for supplying current to the telephone line, the telephonereceiver at said station having two receiver energizing circuits inparallel relation with each other and in serial relation with the line.-and both adapted to be traversed by direct current from said source ofdirect current, to energize the-receiver, one of said windings servingto permit of the passage of voice currents.

15. A telephone system including a telephone line extending between atelephone station and an exchange, a source of direct current at theexchange rent'to the telephone line, the telephone receiver at saidstation including a magnetizfor supplying cur' able core and having twocircuits in parallel relation with each other and in serial relationwith the line and both adapted'to be traversed by current from saidsource of direct current, and each including a winding serving tomagnetize the receiver core,

due to the of said win sage of voice currents, the nvhich is subject tothe voice currents possessing lower ohmic resistance than the companionreceiver circuit. 16.-A telephone system including a telephone lineextending between a telephone station and an exchange, a source ofdirect current at the exchange for sup lying current to the telephoneline, the te ephone re ceiver at said station having two receiverenergizing circuits in parallel relation with each other and in serialrelation with the line and both adapted to be traversed by directcurrent from said source of direct current, to energize the receiver,one of said windings serving to permit of the passage of voice currents,the receiver circuit which is subject to the voice currents possessinglower ohmic resistance than the companion receiver circuit. a

' In witness whereof, I hereunto subscribe my name this sixteenth day ofJ anuary A, l).

Eli NEST E.- YAXLEY.

assage of the direct current, one ings serving to permit of the pas-Witnesses:

L. G. Srnon, G. L; CRAGG.

receiver vcircuit DISCLAIMER- 92%,? 1ei.E'7nest E. YawZey, Chicago, Ill.TELEPHONE SYSTEM. Patent dated June 15, 1909. Disclaimer filed January3, 1913, by the assignee, illonarc/z Telephone lllemngfaczf'wingCompany.

Enters his disclaimer To that part of the claim in said specificationwhich is in the following Words, to wit:

9. A telephone system including a telephone line extending between atele phone station and an exchange, a source of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at said station including a Inagnetizable core and having twocircuits in parallel relation with each other and in serial relationwith the line and both adapted to be traversed by current from saidsource of direct current, and each including a winding serving tomagnetize the receiver core, due to the passage of the direct current,one of said windings serving to permit of the passage of voice currents,the transmitter at said station being in serial relation with thecircuits of the receiver taken together, and thereby being adapted to besupplied also with current emanating from the source of direct current.

10. A telephone system including a telephone line extending between atelephone station and an exchange, a source of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at said station having two receiver energizing circuits inparallel relation with each other and in serial relation with the lineand both adapted to be traversed by direct current from said source ofdirect current, to energize the receiver, one of said windings servingto permit of the passage of voice currents, the transmitter at saidstation being in serial relation with the circuits of the receiver takentogether, and thereby being adapted to be supplied also with currentemanating from the source of direct current.

13. A telephone system including a telephone line extending between atelephone station and an exchange, a source of direct current at theexchange for supplying current to the telephone line, the telephonereceiver at said station including a magnetizable core and having twocircuits in parallel relation with each other and in serial relationwith the line and both adapted to be traversed by current from saidsource of direct current, and each including a winding serving tomagnetize the receiver core, due to the passage of the direct current,one of said windings serving to permit of the passage of voice currents.

14s. A telephone system including a telephone line extending between atelephone station and an exchange, a source of direct current at theexchange for sup plying current to the telephone line, the telephonereceiver at said station having two receiver energizing circuits inparallel relation with each other and in serial relation with the lineand both adapted to be traversed by direct current from said source ofdirect current, to energize the receiver, one or said windings servingto permit of the passage of voice currents.

[Ojicial Gazette, January 14, 1913.]

